Sprawl has long been blamed for a host of social and environmental evils—from the loss of agriculture and natural habitat to the deterioration of older neighborhoods to economic segregation.
At the same time, environmental groups and community activists have been complaining for years about the unhealthy effect sprawl—which forces people to spend more time in their cars—has on air quality, water quality and, consequently, human health.
But the public health argument always seems to get lost in politically charged debate over sprawl versus smart growth.
Last week the Centers for Disease Control and Prevention released a report linking sprawl with a whole array of public health problems: asthma, obesity, depression, anxiety and domestic violence.
The report marks a new focus among public health officials on the impact land use planning has on our physical and mental well-being. It also may be a boost to anti-sprawl activists who want to take the case for smart growth to the mainstream.
The CDC report, “Creating a Healthy Environment: The Impact of the Built Environment on Public Health,” ties together several older studies into one overarching conclusion: sprawl is unhealthy.
That message hit home with Glennah Trochet, public health officer for Sacramento County, who helped unveil the new report last week at the Capitol, along with representatives from the Sierra Club, smart-growth advocacy groups and Assemblyman Darrell Steinberg.
“Over the course of the 20th century, we have built our cities around cars instead of people,” said Trochet. “Land use planners can do a lot more to protect our health.”
The most striking effect of sprawl appears to be its impact on air quality and respiratory disease. The CDC report cites a study of traffic and asthma attacks during the summer Olympics in Atlanta five years ago.
Atlanta city officials aggressively discouraged people from driving their cars during the Olympics, and encouraged citizens to take public transit. It worked. Automobile trips dropped 23 percent, and daily ozone concentrations dropped 28 percent. During the same period, asthma-related emergency room visits fell by 42 percent.
Sprawl also has a connection to increasing levels of obesity. Over the last three decades, as the suburbs have become farther flung and automobile dependence has increased, we’ve become fatter. The percentage of adults who are overweight or obese has risen from 47 to 61 percent since 1976. The prevalence of overweight children and adolescents doubled during the same period.
The report suggests many health problems stem from the fact that our communities are far less “walkable” than ever before. Not only do home, school, work and services tend to be separated by ever-greater distances, but those distances are increasingly hostile to pedestrians and bicyclists.
Narrow sidewalks, or no sidewalks, lack of tree cover, and the concentration of destinations around freeways make walking or biking unpleasant and dangerous.
In Sacramento County, pedestrians make up 21 percent to 28 percent of traffic fatalities every year. But walking accounts for 5 percent of the trips people in Sacramento County make every day.
But I drive to the gym every day, you say. It’s not the same, Trochet said. Many health officials recommend that adults get at least 30 minutes of exercise a day. Most people don’t find time to go to the gym every day.
“It’s very unrealistic to tell people to set time aside for exercise. We really should be getting our exercise on the way to work,” said Trochet.
To get people to walk or bike, planners could insist on more compact growth, fewer houses on isolated cul-de-sacs, and an array of amenities: trees, crosswalks and street medians.
Perhaps the most intriguing part of the CDC report is the link it makes between sprawl and mental health.
The report cites work done by researchers in Chicago who found that people in public housing that was surrounded by green space and trees felt a stronger sense of community, and were less likely to resort to violence to resolve conflicts with neighbors and in the home.
A strong sense of community, often lost in the sprawling anonymous suburbs, may help to ward off anxiety or depression. Add to that the emotional problems associated with lack of exercise, the report concludes with what many have been saying all along: sprawl is depressing.
Trochet acknowledged that land use decisions are ultimately up to elected officials. Which means politics, more than science, determines how we build our communities.
“But it’s my job as a public health official to speak up when public health is threatened. We need to participate in a dialogue with planners and the community,” said Trochet.
Planners have always been charged with protecting the public health. Much of the early impetus behind zoning laws in the early 20th century was to protect health by separating residential and industrial land uses.
And modern day planners try to take into account air quality, water quality, “walkability” and connectedness when they review development proposals.
“We’ve been talking the talk, and trying to get these things implemented for years,” said Tom Hutchings, director of the Sacramento County Planning Department.
Despite incremental improvements over the years, politics and economics frequently cause local governments to compromise sound planning principles.
The public health community, said Hutchings, could go a long way toward raising public awareness, and convincing people that how we design our neighborhoods is more important than they might realize.
“And when the community embraces those principles,” Hutchings said, “it’s a lot easier to implement.”